Within the field of medicine many different medical related tasks involve delivery and/or removal of air to and from a patient's medical device. A common example is a pneumatic compression device. The medical devices used in pneumatic compression typically require a direct connection from the air supply device to the device connected to the patient in the form of a tube. Depending on their intended use, the tube designs can vary in characteristics such as size (length, inner and outer diameter), hardness, flexibility, compressibility, and durability. These characteristics are dictated by the choice of material from which the tube is formed, with polyvinylchloride (PVC), polyurethane (PU), silicone and latex rubber being quite commonplace.
One of the most critical concerns whenever a tube is used in a medical device is that its lumen remains patent. If the lumen decreases or collapses, the transmission of the air slows or ceases, presenting in many circumstances a medical emergency or at least a situation of medical concern. Physical folding or compression of the tube can occlude the lumen quite easily in many situations.
In a majority of medical pneumatic device applications, a key characteristic of the tube is flexibility. It needs to be moveable and maneuverable to facilitate connection from the device to the patient, as device and patient location and position can vary widely. However, by increasing tubal flexibility, usually by adding plasticizers or other known additives, there is a softening effect in the composite material, which also increases compressibility, and thereby increases the occlusion potential of the tubal lumen. One way this occluding can happen is if the patient accidently compresses the device tube by lying on, sitting on, rolling over on, or by bending a segment of the flexible tubing too far, thus pinching the lumen closed. Manufacturing a thicker tube wall can help remedy these situations, but brings added cost and decreased tubal flexibility. Additionally, smaller diameter tubes still remain flexible and tend to have fewer problems associated with bending and compression of the lumen, but are not suited for all situations, especially those situations requiring the transfer of lower density fluids at higher flow rates, as in the case of air transmission.
Intermittent pneumatic compression therapy (“CPC”) as a preventive treatment for deep vein thrombosis (“DVT”) incorporates the use of flexible tubes transferring air from an air pump to inflate and deflate airtight garments wrapped around a patient's limb. The flexible tubes attach to the air pump and garment on the patient, via industry-standard tube connectors. The successive inflations and deflations of the garment simulate the series of compressions applied to the limb veins during normal muscle contractions, and thereby limit any blood stasis that could lead to the formation of clots (“thrombi”). IPC can be of benefit to patients deemed to be at risk of deep vein thrombosis during extended periods of inactivity, and is an accepted treatment method for preventing blood clots or complications of venous stasis in persons after physical trauma, orthopedic surgery, neurosurgery, or in disabled persons who are unable to walk or mobilize effectively. This technique is also used to stop blood clots from developing during surgeries that will last for an extended period of time.
Complications from use of the IPC device can arise particularly, if the airtight garments around the patient's limb do not deflate, leaving a prolonged state of increased pressure on the limb. This tourniquet-like effect can impede normal blood flow, and thus create other problems such as swelling and improper tissue oxygenation toward the end of the limb, as well as increasing the risk of thrombi formation. This improper deflation of the IPC garment can occur if the tube from the air pump to the inflatable garment is occluded, such as can happen if a patient accidentally lies or sits on the tube or the tube gets inadvertently compressed or bent as can happen when the patient is sleeping, for example. Another cause of improper deflation is failure of the air pump to release air from the tube. Some tubes in the industry are manufactured with a denser, less compressible material, usually metal, coiled within or lined the inside of their was to prevent collapse or occlusion of the tubal lumen. These tubes can be effective in restricting occlusion; however, they are significantly more complex in design and require more costly manufacturing and production processes.
In light of the above, it would be advantageous to provide a connector with a micro bleed hole that connects an air tube to the IPC garment on the patient, and safely allows deflation of a medical or therapy device in the event such device fails due to an occluded air tube or inoperative air pump. It would be further advantageous to provide a connector with a micro bleed hole that is easily manufactured from current industry-standard connectors occurring in a variety of sizes and styles that can be easily inserted into tubes of the types and grades already commonly used in the medical and therapy industries. It would also be advantageous to provide a micro bleed hole connector for medical and therapy device air tubes that is easy to use and customize, relatively easy to manufacture, and comparatively cost efficient.